//yzx
#include<bits/stdc++.h>
using namespace std;
int n,m,b;
char mapp[25][25];
void dfs(int x,int y){
	if(x==n&&y==m){
		b=1;
	}
	if(mapp[x][y]=='#'){
		return;
	}
	dfs(x+1,y);
	dfs(x-1,y);
	dfs(x,y+1);
	dfs(x,y-1);
}
int main(){
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin>>mapp[i][j];
		}
	}
	dfs(n,m);
	if(b==1){
		cout<<"Yes";
	}else{
		cout<<"No";
	}
	return 0;
}